S. No. | Source | Method of preparation | Doping (d)/surface passivating (p) agent | Color | Size (nm) | Refs. No. |
---|---|---|---|---|---|---|
1. | Citric acid, N-(β-Aminoethyl)-γ-aminopropyl methyl dimethoxy silane | Thermal decomposition | AEAPMS (P) | Blue | 0.9 | [82] |
2. | Citric acid | Thermal decomposition | DETA (p) | Blue | 3–5.5 | [84] |
3. | Citric acid | Thermal decomposition | Ruthenium (III) | Blue | 6.8 ± 2.3 | [85] |
4. | Citric acid | Thermal decomposition | – | Blue | 0.7–1.0 | [34] |
5. | l-Cysteine | Thermal decomposition | 1-butyl 3-methyl imidazolium bromide | Blue, yellow, red, green | 1.0–3.5 | [83] |
6. | Citric acid | Thermal treatment | Dicyanamide (d) | Green | 8–16 | [86] |
7. | Glucose | Carbonization | Ethylene diamine (d), phosphoric acid (p) | Green | 1–7 | [87] |
8. | Citric acid | Carbonization | – | Blue | 4.8–9 | [88] |
9. | 6-O-(O–O-dilauroyl-tartaryl)-d-glucose | Carbonization | – | Green | 2.4 ± 0.5 | [89] |
10. | Tris base, betaine Hcl | Pyrolysis | Gadopetetic acid (d) | Purple, Green | 3.2 | [31] |
11. | GDs | Pyrolysis | l-glutamic acid | Blue, green and red | 4.66–1.24 | [17] |
12. | d-Glucose | Pyrolysis | l-Aspartic acid (d) | Yellow | 2.28 ± 0.42 | [90] |
13. | Sodium alginate | Pyrolysis | – | Blue | < 10 | [91] |
14. | Citric acid | Pyrolysis | Diethylenetriamine (p) | Indigo | 5–8 | [11] |
15. | CCl4, NaNH2 | Solvothermal method | N (d) | Blue, cyan, kelly, and yellow | 3.3 | [36] |
16. | SiCl4, hydroquinone | Solvothermal treatment | Si (d) | Blue | 7 ± 2 | [29] |
17. | hydroquinone | Solvothermal method | BBr3 (d) | Blue | 16 | [15] |
18. | Glucose, HCl/NaOH | Ultrasonic treatment | – | Blue | < 5 | [30] |
19. | Active carbon, H2O2 | Ultrasonic treatment | – | Blue, green, yellow, red | 5–10 | [92] |